The extended
voltage range (3.22 – 4.5V) represents the maximum and minimum voltages
can be applied to the module without damaging it or causing a shut
down. The hw user guide indicates as Normal Operating range the limits
used for Type Approval (3.4 – 4.2V )

The extended voltage range can be used only with a very stable power
supply taking care of every recommendation and suggestion present in our
HW User guide.